Saturday, January 25, 2020

Enzyme Activity As A Function Of Substrate Concentration Biology Essay

Enzyme Activity As A Function Of Substrate Concentration Biology Essay The effect of concentration on enzyme activity. It can be noted that both enzyme solution used had different results. Enzyme activity was greater when using the chicken liver rather than the cow liver. Generally the enzyme activity increases as the drops of the enzyme (concentration) increases. There was a significant increase when six drops of enzyme solution (chicken liver) was added. The height of the bubble rose to 4 cm. there was a steady increase between when 9-12 drops solution was added. A sharp increase occurred when 15 drops of enzyme solution was added. The height was recorded as 7.5 cm. There was no significant increase onwards When enzyme solution (cows liver) was added there was no significant increase in the first set of drops. The height was recorded to be 3.5 cm when 3 drops of enzyme solution was added. There was an increase from 3.5 to 4cm when 6 drops of solution was added. There were no further significant increases un adding the enzyme solution. Graph 2 shows the effect of temperature on enzyme activity. For this experiment an enzyme solution of cow liver was used. There was an increase in bubble height when the solution was placed at 25 C. There was a further increase in the height when the solution was placed at 50 C. The height was recorded as 4.2 cm. However at 70 C, there was no change. There was no evidence of bubbles suggesting that the enzyme had been denatured. EXPLANATION Generally enzyme activity increases with increasing temperature. However in this experiment there was an increase then a sudden drop in enzymatic activity. Enzymes require certain conditions to be effective in their functioning. Some require certain temperatures to function. A reason behind the denaturing of the enzyme at 70 C is that the temperature was too high for the enzyme to function and it denatured due to this. Factors Affecting Enzyme Activity Knowledge of basic enzyme kinetic theory is important in enzyme analysis in order both to understand the basic enzymatic mechanism and to select a method for enzyme analysis. The conditions selected to measure the activity of an enzyme would not be the same as those selected to measure the concentration of its substrate. Several factors affect the rate at which enzymatic reactions proceed temperature, pH, enzyme concentration, substrate concentration, and the presence of any inhibitors or activators. Temperature Effects http://www.worthington-biochem.com/IntroBiochem/images/ie21.gif Like most chemical reactions, the rate of an enzyme-catalyzed reaction increases as the temperature is raised. A ten degree Centigrade rise in temperature will increase the activity of most enzymes by 50 to 100%. Variations in reaction temperature as small as 1 or 2 degrees may introduce changes of 10 to 20% in the results. In the case of enzymatic reactions, this is complicated by the fact that many enzymes are adversely affected by high temperatures. As shown in Figure 13, the reaction rate increases with temperature to a maximum level, then abruptly declines with further increase of temperature. Because most animal enzymes rapidly become denatured at temperatures above 40Â °C, most enzyme determinations are carried out somewhat below that temperature. Over a period of time, enzymes will be deactivated at even moderate temperatures. Storage of enzymes at 5Â °C or below is generally the most suitable. Some enzymes lose their activity when frozen. Effects of pH Enzymes are affected by changes in pH. The most favorable pH value the point where the enzyme is most active is known as the optimum pH. This is graphically illustrated in Figure 14. http://www.worthington-biochem.com/IntroBiochem/images/ie22.gif Extremely high or low pH values generally result in complete loss of activity for most enzymes. pH is also a factor in the stability of enzymes. As with activity, for each enzyme there is also a region of pH optimal stability. The optimum pH value will vary greatly from one enzyme to another Enzyme Concentration In order to study the effect of increasing the enzyme concentration upon the reaction rate, the substrate must be present in an excess amount; i.e., the reaction must be independent of the substrate concentration. Any change in the amount of product formed over a specified period of time will be dependent upon the level of enzyme present. Graphically this can be represented as: http://www.worthington-biochem.com/IntroBiochem/images/ie09.gif These reactions are said to be zero order because the rates are independent of substrate concentration, and are equal to some constant k. The formation of product proceeds at a rate which is linear with time. The addition of more substrate does not serve to increase the rate. In zero order kinetics, allowing the assay to run for double time results in double the amount of product. The amount of enzyme present in a reaction is measured by the activity it catalyzes. The relationship between activity and concentration is affected by many factors such as temperature, pH, etc. An enzyme assay must be designed so that the observed activity is proportional to the amount of enzyme present in order that the enzyme concentration is the only limiting factor. It is satisfied only when the reaction is zero order. Enzyme activity is generally greatest when substrate concentration is unlimiting. Effects of Inhibitors on Enzyme Activity Enzyme inhibitors are substances which alter the catalytic action of the enzyme and consequently slow down, or in some cases, stop catalysis. There are three common types of enzyme inhibition competitive, non-competitive and substrate inhibition. Most theories concerning inhibition mechanisms are based on the existence of the enzyme-substrate complex ES. Competitive inhibition occurs when the substrate and a substance resembling the substrate are both added to the enzyme. A theory called the lock-key theory of enzyme catalysts can be used to explain why inhibition occurs. The lock and key theory utilizes the concept of an active site. The concept holds that one particular portion of the enzyme surface has a strong affinity for the substrate. The substrate is held in such a way that its conversion to the reaction products is more favorable. If we consider the enzyme as the lock and the substrate the key the key is inserted in the lock, is turned, and the door is opened and the reaction proceeds. However, when an inhibitor which resembles the substrate is present, it will compete with the substrate for the position in the enzyme lock. When the inhibitor wins, it gains the lock position but is unable to open the lock. Hence, the observed reaction is slowed down because some of the available enzyme sites are occupied by the inhibitor. If a dissimilar substance which does not fit the site is present, the enzyme rejects it, accepts the substrate, and the reaction proceeds normally. ACTIVE SITE This is the part of an enzyme or antibody where the chemical reaction occurs SUBSTRATE In biochemistry, a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate(s). In the case of a single substrate, the substrate binds with the enzyme active site, and an enzyme-substrate complex is formed. The substrate is transformed into one or more products, which are then released from the active site ENZYME SUBSTRATE COMPLEX This is when the substrate binds reversibly to the enzyme forming a complex ANABOLISM Anabolism, or biosynthesis, is the process by which living organisms synthesize complex molecules of life from simpler ones. Anabolism, together with catabolism, are the two series of chemical processes in cells that are, together, called metabolism. Anabolic reactions are divergent processes. That is, relatively few types of raw materials are used to synthesize a wide variety of end products. This results in an increase in cellular size or complexity-or both. Anabolic processes produce peptides, proteins, polysaccharides, lipids, and nucleic acids. These molecules comprise all the materials of living cells, such as membranes and chromosomes, as well as the specialized products of specific types of cells, such as enzymes, antibodies, hormones, and neurotransmitters. CATBOLISM Catabolism, the opposite of anabolism, produces smaller molecules used by the cell to synthesize larger molecules, as will be described below. Thus, in contrast to the divergent reactions of anabolism, catabolism is a convergent process, in which many different types of molecules are broken down into relatively few types of end products. ..

Friday, January 17, 2020

Copper Cycle

The Copper Cycle Most of the background material for this laboratory will be covered in greater detail in the lecture course later in the semester. Here is some background information so you will understand the chemistry behind the reactions you will perform. Many aspects of our lives involve chemical reactions-?from the batteries that power our cars and cell phones to the thousands of processes occurring within our bodies. Most of these reactions can be classified into one of three main types of chemical reactions: precipitation reactions, acid-base naturalization reactions, and oxidation- deduction (also called â€Å"redo†) reactions.Aqueous Solutions(as) Many reactions occur in an aqueous environment (I. E. , in a solution where ions and compounds are dissolved in water). When we indicate that a reactant or product has the physical state (as), we mean the substance is dissolved in water. When an ionic compound is in aqueous solution, the individual ions are present in solut ion; for example, NCAA(as) exists as An+ and CLC- ions moving around in water. Solubility Rules Many ionic compounds are soluble-?I. E. , they dissolve in water.Others generally do not dissolve in water and are considered insoluble. To determine if an ionic compound is soluble-?I. E. , will dissolve-?in water, we use the Solubility Rules: Solubility Rules for Ionic Compounds in Water The compound is SOLUBLE if it has: An+, NH 4+ ton (ALWAYS! ) 2. CHICHI-, NON-, CHIC- 3. CLC-, BRB-, or 1-, except compounds with Gag+, BP+2, and Hag+2 are insoluble 4. SASS- except compounds with Saga's, cases, scars, Bases, PBS, and Haggis are insoluble The compound is INSOLUBLE if it has: 5.CHIC-, crack-, IPPP-, except compounds with Lie+, An+, K+, NH+ are soluble 6. SO-, except compounds with Lie+, An+, K+, NH+, ca+2, sir+2, AAA+2 are soluble . Hydroxide ion, OH-, except compounds The Solubility Rules indicate which compounds are soluble, and thus are represented as aqueous: e. G. , Kill(as), Abaca(a s), Noah(as), etc. The Solubility Rules also indicate which compounds are insoluble-?I. E. , do not dissolve in water and remain as solids: e. G. Basso+), Call(s), cacao(s), etc.Double Replacement/Precipitation Reaction For example, consider the reaction between aqueous lead(al) nitrate with aqueous potassium bromide, as shown below: KGB(as) Puff KNEE Note that the chemical formulas for the products formed are based on their charges, to how they appear on the reactant side of the chemical equation. ICC CHEM. 151 AL: The copper cycle O ICC, 2013 page 1 of 12 Based on Solubility Rules #4 and #1, we find that BRB is insoluble and KNEE is soluble.Thus, the complete, balanced equation is: + 2 KGB(as) Pacific) + 2 KNEE(as) We can cancel the spectator ions from the ionic equation and write the net ionic equation: Pub+(as) + 2 BRB -(as) 0 BRB(s) This reaction produces a cloudy mixture with small particles of the solid suspended in the solution. When enough solid has formed, it will begin to settle at the bottom of the beaker. Thus, a clear solution becoming cloudy when another solution is added is often taken as experimental evidence of a solid or precipitate forming.Acids and Bases Acids can be defined as substances that produce hydroxide ions (HUH+) when they are dissolved in water. A hydroxide ion is the product of a hydrogen ion that reacts with a water molecule: H+(as) + H2O(l) 0 HUH+(as). A hydrated hydrogen ion (H+(as)) is equivalent to an aqueous hydroxide ion. The two equations below both represent the unionization of hydrochloric acid, HCI(as), but the second one shows a particular water molecule explicitly. HCI(as) O H+(as) + CLC-(as)HCI(as) + H2O(l) O HUH+(as) + CLC-(as) Acids are usually easy to recognize since their formulas start with H and contains nonmetal elements other than H-?e. G. HCI(as), HON.(as), and HASPS(as) are all acids. Note that the physical state aqueous, (as), must be included to distinguish a compound that is acting like an acid from o ther forms of a substance. For example, the formula â€Å"HCI† can also be used for hydrogen chloride gas, HCI(g), so to indicate aqueous hydrochloric acid, one must specify HCI(as). One useful definition of bases is that bases are compounds that produce hydroxide ions (OH-) when dissolved in water.The dissociation of sodium hydroxide, Noah, is shown below. : Noah(s) Noah(as) which is equivalent to An+(as) + OH-(as) Acid-Base Naturalization Reactions In an acid-base naturalization reaction, a hydrogen ion-containing acid reacts with a hydromechanics's base to produce water and a salt (an ionic compound): HCI(as) + Noah(as) O acid base H2O(l) + Niacin(as) water salt Acids can react with bases, regardless of whether the salt is soluble or insoluble. There are other types of acids and bases that can react without forming water.If the reactants and products of an acid/base reaction are colorless and soluble, it is impossible to monitor the progress of an acid-base reaction based solely on the appearance of the solutions. To help us monitor acid-base reactions, we use litmus paper to determine if a solution is acidic or basic. Litmus paper changes color depending on the presence of H+ or OH- ions in the substance being tested. Blue litmus paper turns red in acidic solutions containing H+ ions, and red litmus paper turns blue in basic solutions containing OH- ions. Age 2 of 12 Oxidation/Reduction Reactions In an oxidation/reduction reaction, electrons are transferred from one reactant to the other. In the simplest form of these reactions, single-displacement reactions (also called single-replacement reactions), metal ions react with pure metals. If the reaction proceeds, the pure metal gives electrons to the metal action. This causes the pure metal to become a action and the action to become a pure metal. The action must always have an anion partner which is present either in an ionic solid or in a solution.For example: MGM(s) + 2 Gag+(as) 0 2 Gag(s) + MGM+(a s) metal action If the charge of an element is changing, that is a good indication that an oxidation/ reduction reaction is taking place. Later in the semester you will learn about oxidation numbers which are used to keep track of more complicated oxidation/ reduction reactions. Step l: Chemistry The different copper species obtained in each part is shown in Equation 1 below: cue(S) Part I cue+(as) Part II part Ill cue(S) part Part V blue l.Oxidation Copper Metal with Concentrated Nitric Acid, HON.(as) The first step involves transforming Cue metal to copper(al) ions, Cue+, using concentrated nitric acid, HON.(as). At the same time, the nitrate ions (NON-) undergo a series of reactions to form nitrogen monoxide, NO. This product rapidly reacts with oxygen in the air to form NON, a brown gas. The presence of Cue+(as) makes the solution blue. When the reaction mixture is diluted with water, the Cue+ ions are hydrated (surrounded by water) to form the octahedral complex ion, [Cue(H2O)6 ]2+, as shown below.Six water molecules (shown as red O and white H atoms) are bonded to a Cue+ ion (shown in gray as the central atom). Cue+(as) + 6 H2O(l) 0 [Cue(H2O)6]2+(as) Figure 1 page 3 of 12 Step II: Chemistry II. Precipitating Cue(OH)2(s) with Noah(as) In Part II, two reactions are carried out by adding Noah(as). In the first reaction, the hydroxide ions (OH-) from the Noah(as) neutralize the excess hydroxide ions (HUH+) feet over from the previous part: HUH+(as) + OH-(as) 2 H2O(l) Once all the HUH+ ions are neutralized, additional OH- ions react with the Cue+ ion to form Cue(OH)2 precipitate. Once all the Cue+ ions have reacted, no more precipitate forms.Adding more OH- ions makes the solution basic, so it can turn red litmus paper blue. Figure 2 on the next page shows the step-wise reaction of Cue+ with Noah. Figure 2: Step-wise Illustration of the Precipitation of Cue(OH)2 in Part II – Remember: [Cue(H2O)]2+ indicates the same substance as Cue+. 1st Beaker: At the end of Part I, hydrated copper complex, Cue+ are present, making he solution blue, and excess hydroxide ions (HUH+) remain from the nitric acid used. 2nd Beaker: Adding Noah(as) to the blue solution results in the OH- ions neutralizing the HUH+ ions to form water: HUH+(as) + OH-(as) 0 2 H2O(l).The An+ ions and resulting water molecules are not shown. 3rd and 4th Beakers: Once all the HUH+ are neutralized, adding more Noah(as) results in the OH- ions reacting with the Cue+ to form the blue Cue(OH)2(s) precipitate shown at the bottom of the beaker. Water molecules released from the complex ion are not shown. 5th Beaker: When all of the Cue+ ions have been converted to Cue(OH)2(s) precipitate, adding more Noah(as) results in unrelated OH- ions in solution, which makes the solution basic. Red litmus paper can be used to confirm the solution is basic.Note that the solution is no longer blue since no Cue+ ions are present in the solution. Step Ill: Chemistry Ill. Converting solid Cue(OH) 2 to solid Cue In Part Ill of the sequence, the reaction mixture is heated. This transforms the Cue(OH)2 precipitate to Cue precipitate. Page 4 of 12 The Cue precipitate is separated from the solution, called the supernatant liquid, using a method called gravity filtration. The mixture is filtered using a filter funnel, ND the solid is collected on filter paper. The supernatant liquid runs through the filter paper and collects in a beaker.This resulting filtered solution is called the filtrate. Step IV: Chemistry ‘V. Dissolving Cue(s) with sulfuric acid, HASPS(as) In Part ‘V, the Cue precipitate is dissolved using sulfuric acid, HASPS(as). This redo reaction returns copper to its aqueous phase. Step V: Chemistry V. Reducing Cue+ ions with Zinc Metal In Part V, zinc metal (Zen) is added to the copper solution to convert the copper ions back to copper metal, Cue(s). The resulting solution will contain colorless zinc ions, Zen+(as) and copper solid. Visible evidence of this reaction is observed as bubbles of gas being released from the solution. Since the HUH+ ions do not dissolve the Cue metal, the amount of copper yielded is not affected by excess acid. ) Identify the gas displaced from the acid in this reaction. When the solution becomes colorless, all of the Cue+ ions have been converted to Cue metal. All of the excess Zen metal is also converted to Zen+ ion by the excess HUH+ ions from the sulfuric acid, HASPS(subdued to dissolve the Cue precipitate in Part IV. Once all the Zen metal is dissolved, the Cue metal can be isolated by decanting, or pouring off, the supernatant liquid. The Cue will then be rinsed, dried, and weighed as described in the procedure. Age 5 of 12 In this experiment, you will carry out a series of reactions starting with copper metal. This will give you practice handling chemical reagents and making observations. It is typical for scientists to observe materials before they react, what happens during a reaction and how it lo oks when the reaction has come to completion. The product of the final reaction will be copper metal and the percent copper that is recovered will be calculated. **Lab Notebook** You should include one table that contains the mass of copper at the beginning and ND of the experiment along with % of copper recovered.This table should include: Mass of copper at the start of experiment (in Part l) Mass of copper + evaporating dish (from Part V) Mass of empty evaporating dish (from Part V) Mass of copper recovered (from Part V) Percent of copper recovered Record observations for each of the steps (I-V) of the copper cycle in your lab book. Be sure to label each step (I-V). The observations for each step should include: the appearance of the reactants before the reaction the appearance of the reactants during the reaction (for example, bubbles, flames, etc. The appearance of the products after the reaction.Your observations should include state(s) of matter, color, texture, smell, etc. Wh ere applicable. If your observations are not detailed, you may not receive full credit. One step also requires a specific chemical test using litmus paper to check for acidity. Be sure to also record the results of these tests in your lab notebook. **You will turn in worksheet pages 11-12 along with the duplicate pages from your lab notebook. Step l: Procedure – Oxidation Cue with concentrated nitric acid, HON.(as) 1 . Place a sample of weighing paper in the balance. Tare the balance, so it reads 0. 0000 g. Use forceps to transfer about 0. 5-0. 40 g of Cue strips onto the weighing paper. Record the mass of the Cue strips. Transfer the Cue strips into a clean 250-ml beaker labeled with one of your group member's initials. Record the appearance of the copper metal in your lab report. CAUTION: Concentrated nitric acid is highly corrosive, so it can cause severe chemical burns and damage clothing. Handle with care and avoid breathing the fumes. Any nitric acid spilled on skin mus t be rinsed immediately with water for 15 minutes. Any acid spilled on your work area must be neutralized then the entire rear should be washed and dried.CAUTION: Concentrated nitric acid reacts with copper metal to form brown toxic NON gas. Leave the reaction beaker in the fume hood until all of the brown gas is vented in the hood. ICC CHEM. 151 AL: The Copper Cycle page 6 of 12 2. In a fume hood, use a 10-ml graduated cylinder to carefully measure about 3 ml of concentrated nitric acid, HON.(as). Slowly pour the nitric acid onto the Cue strips in the beaker, swirling the beaker to maximize contact between the Cue and nitric acid until all of the solid Cue has dissolved and the NON gas has escaped.Keep the action beaker in the hood until all the toxic brown NON gas is gone, and keep your face away from the hood to avoid inhaling nitric acid fumes and NON gas. Describe the reaction between HON. and the Cue metal in your lab report. 3. Dilute the resulting solution with about 10 ml o f denizen water. Describe the appearance of the resulting solution containing Cue+ in your data table. Step II: Chemistry – Precipitating Cue(OH)2(s) with Noah(as) left over from the previous part. Once all the HUH+ ions are neutralized, additional OH- ions react with the Cue+ complex ion to form a gelatinous blue Cue(OH)2 precipitate.Once all the Cue+ ions have reacted, no more precipitate forms. Adding more OH- ions makes the solution basic, so it can turn red litmus paper blue. The picture sequence on the next page outlines the step-by-step process that occurs during this step. Step II: Procedure – Precipitating Cue(OH)2 with Noah solution CAUTION: Sodium hydroxide (Noah) can easily damage eyes. It is corrosive and can cause chemical burns and damage clothing. Any Noah splashed into eyes or spilled on skin must be rinsed immediately with water for 15 minutes. Any base spilled on your work area must be neutralized then the entire area should be washed and dried. Whil e constantly stirring the Cue solution, slowly add MM Noah(as) from the dropper bottles. First, the OH- from the Noah added will neutralize the excess acid left over from Part l. 2. Once all the acid is neutralized, additional OH- ions react with the Cue+ to form Cue(OH)2(s), a blue precipitate. Record what you observe in your lab report. When adding more Noah does not produce more precipitate, the solution can be tested to determine if all the Cue+ has been precipitated and additional OH- has made the solution basic. Use red litmus paper to test if the solution is basic as follows.Without stubbing any precipitate, use a glass stir rod to place a drop of solution (NOT the precipitate) on a piece of red litmus paper. If it turns blue, the solution is basic. Stop adding Noah when the solution turns red litmus paper blue. Describe your litmus test in your lab report. Page 7 of 12 Step-wise Illustration of the Precipitation of part II 1st Beaker: Check solution using red litmus paper (r efer to background handout). Continue adding base until solution is basic. At the end of Part I Cue+ ions are present, making the solution blue, and excess hydroxide ions (HUH+) remain from the nitric acid used. D Beaker: Adding Noah(as) to the blue solution results in the OH- ions ions are not shown. 3rd and 4th Beakers: 5th Beaker: Once all the HUH+ are neutralized, adding more Noah(as) results in the OH- ions reacting with the Cue+ to form the blue Cue(OH)2(s) precipitate shown at the bottom of the beaker. When all of the Cue+ ions have been converted to Cue(OH)2(s) precipitate, adding more Noah(as) results in unrelated OH- ions in solution, which makes the solution basic. Red litmus paper can be used to confirm the solution is basic. Note that the solution is no longer blue since no Cue+ ions are present in the solution.In reality, your solution may still appear blue because of the dispersion of the Cue(OH)2 in the solution by mixing. Step Ill: Procedure – Converting Cue( OH)2(s) to Cue(s) 1. Set up a ring stand as shown in the figure at the right. Set up a ring clamp, and put a wire gauze on top of it. Above it, attach another ring clamp with a diameter large enough to go around a 250-ml beaker. You are going to set your 250 ml beaker on the lower ring and gauze. The upper clamp will hold the beaker in place so it does not fall. 2. Add about 30-40 ml of denizen water to your reaction beaker from Part II.Carefully place the beaker on the ring stand inside the upper ring. CAUTION: Gently heat the beaker over a medium flame. (Set the inner cone of the Bunsen burner flame to a height of about 1. 5 inch and the lower ring stand about 4 inches above the top of the Bunsen burner). Constantly stir the solution with the glass end of the stirring rod until all the blue precipitate turns black, and the solution is clear. If the solution starts to bump or boil, immediately remove the beaker from the heat and let the solution cool slightly. Describe what happens to the Cue(OH)2 precipitate upon heating in your lab port. Age 8 of 12 3. Allow the beaker and contents to cool. While they are cooling, set up the gravity filtration apparatus. Obtain a second ring stand, and attach a ring clamp that is small enough to hold the plastic funnel. Prepare the filter paper as shown below: Finally, place the plastic funnel in the small ring clamp, and place a 400-ml beaker beneath it to collect the filtrate (the liquid that goes through the filter paper). The funnel's stem should be Just inside the beaker to prevent splashing. 4. Use the markings on a clean 150-ml beaker to measure out about 25 ml of denizen water.Boil the water on a hotplate to wash the precipitate in step 6. 5. When the 250-ml reaction beaker has cooled to room temperature, pour the Cue precipitate into the funnel to filter the contents. Transfer the last traces of the solid from the reaction beaker into the funnel, using a stream of denizen water. 6. Use a disposable pipette to wash the precipitate on the filter paper using the hot denizen water heated in the 150-ml beaker. Allow each portion of hot water to drain through the filter paper into the beaker below before adding the next portion. Use 15 ml of the hot denizen water to thoroughly wash the Cue precipitate. Copper Cycle CH 130 B: General Chemistry I The Lab Report As a scientist you are responsible for conveying the results of an experiment to a supervisor, a colleague, or the public. Often, you will convey this information in the form of a scientific paper describing your work. This paper needs to clearly describe why and how an experiment was done, and it must include an interpretation of results, including a discussion of their importance and any significant sources of error. You lab report will be a brief version of a publication.It should contain the following sections: Introduction This part of the paper should be an explanation of the purpose of the experiments and a review of relevant principles related to the work. This is NOT a procedure. Data and Calculations Attach your graded summary sheet from the experiment. If you did any calculations incorrectly, attach a sheet with correct calculations. In addition to the summary sheet include a table which details observations and known informatio n. What did the solutions look like, what were their concentrations, etc.?Results and Discussion This part of the report should include an in-depth discussion of your data and observations, in essay form. Again, do not rewrite a detailed procedure here, but summarize what you did in the experiment. Describe what you observed. What do your results tell you? Explain whether your results matched your expected results. If they didn’t (and they surely didn’t match exactly) discuss the reasons why this might be the case. What are the possible sources of error?How would each of these sources of error affect the result? Convince yourself and your reader that you are correct in your conclusions. Reiterate your data in relation to your conclusions. You should be able to explain the chemistry that is occurring in the experiment. Please remember the basic principles of writing. Your lab report must be mechanically correct (grammar and punctuation). It is your responsibility to che ck your grammar and spelling. You will be graded on this. How is a lab report different than an English paper? Lab reports are written in third person, passive, past tense. †¢ The rough draft and final draft can be double-sided, but they must be double-spaced. †¢ Lab reports use simple, declarative sentences that connect observations to conclusions. †¢ The simplest way to say something is often the best. There is no page or word requirement. Say what you have to say so that your reader understands. Common mistakes to avoid: †¢ Try not to start your introduction with â€Å"the purpose of this experiment† or a similar phrase. Compounds/elements are not proper nouns. Do not capitalize them. †¢ Use superscripts and subscripts. †¢ Proofread!! This lab report should be approximately 2 pages long. You will all write the lab report for the same experiment. The experiment is labeled on your schedule as â€Å"Cu Cycle. † A completed rough draft of y our lab report is due on (or before) October 22. The rough draft will be counted as half of the total grade for the paper. The final draft of your report will be due on November 26 in class. Copper Cycle The Copper Cycle Most of the background material for this laboratory will be covered in greater detail in the lecture course later in the semester. Here is some background information so you will understand the chemistry behind the reactions you will perform. Many aspects of our lives involve chemical reactions-?from the batteries that power our cars and cell phones to the thousands of processes occurring within our bodies. Most of these reactions can be classified into one of three main types of chemical reactions: precipitation reactions, acid-base naturalization reactions, and oxidation- deduction (also called â€Å"redo†) reactions.Aqueous Solutions(as) Many reactions occur in an aqueous environment (I. E. , in a solution where ions and compounds are dissolved in water). When we indicate that a reactant or product has the physical state (as), we mean the substance is dissolved in water. When an ionic compound is in aqueous solution, the individual ions are present in solut ion; for example, NCAA(as) exists as An+ and CLC- ions moving around in water. Solubility Rules Many ionic compounds are soluble-?I. E. , they dissolve in water.Others generally do not dissolve in water and are considered insoluble. To determine if an ionic compound is soluble-?I. E. , will dissolve-?in water, we use the Solubility Rules: Solubility Rules for Ionic Compounds in Water The compound is SOLUBLE if it has: An+, NH 4+ ton (ALWAYS! ) 2. CHICHI-, NON-, CHIC- 3. CLC-, BRB-, or 1-, except compounds with Gag+, BP+2, and Hag+2 are insoluble 4. SASS- except compounds with Saga's, cases, scars, Bases, PBS, and Haggis are insoluble The compound is INSOLUBLE if it has: 5.CHIC-, crack-, IPPP-, except compounds with Lie+, An+, K+, NH+ are soluble 6. SO-, except compounds with Lie+, An+, K+, NH+, ca+2, sir+2, AAA+2 are soluble . Hydroxide ion, OH-, except compounds The Solubility Rules indicate which compounds are soluble, and thus are represented as aqueous: e. G. , Kill(as), Abaca(a s), Noah(as), etc. The Solubility Rules also indicate which compounds are insoluble-?I. E. , do not dissolve in water and remain as solids: e. G. Basso+), Call(s), cacao(s), etc.Double Replacement/Precipitation Reaction For example, consider the reaction between aqueous lead(al) nitrate with aqueous potassium bromide, as shown below: KGB(as) Puff KNEE Note that the chemical formulas for the products formed are based on their charges, to how they appear on the reactant side of the chemical equation. ICC CHEM. 151 AL: The copper cycle O ICC, 2013 page 1 of 12 Based on Solubility Rules #4 and #1, we find that BRB is insoluble and KNEE is soluble.Thus, the complete, balanced equation is: + 2 KGB(as) Pacific) + 2 KNEE(as) We can cancel the spectator ions from the ionic equation and write the net ionic equation: Pub+(as) + 2 BRB -(as) 0 BRB(s) This reaction produces a cloudy mixture with small particles of the solid suspended in the solution. When enough solid has formed, it will begin to settle at the bottom of the beaker. Thus, a clear solution becoming cloudy when another solution is added is often taken as experimental evidence of a solid or precipitate forming.Acids and Bases Acids can be defined as substances that produce hydroxide ions (HUH+) when they are dissolved in water. A hydroxide ion is the product of a hydrogen ion that reacts with a water molecule: H+(as) + H2O(l) 0 HUH+(as). A hydrated hydrogen ion (H+(as)) is equivalent to an aqueous hydroxide ion. The two equations below both represent the unionization of hydrochloric acid, HCI(as), but the second one shows a particular water molecule explicitly. HCI(as) O H+(as) + CLC-(as)HCI(as) + H2O(l) O HUH+(as) + CLC-(as) Acids are usually easy to recognize since their formulas start with H and contains nonmetal elements other than H-?e. G. HCI(as), HON.(as), and HASPS(as) are all acids. Note that the physical state aqueous, (as), must be included to distinguish a compound that is acting like an acid from o ther forms of a substance. For example, the formula â€Å"HCI† can also be used for hydrogen chloride gas, HCI(g), so to indicate aqueous hydrochloric acid, one must specify HCI(as). One useful definition of bases is that bases are compounds that produce hydroxide ions (OH-) when dissolved in water.The dissociation of sodium hydroxide, Noah, is shown below. : Noah(s) Noah(as) which is equivalent to An+(as) + OH-(as) Acid-Base Naturalization Reactions In an acid-base naturalization reaction, a hydrogen ion-containing acid reacts with a hydromechanics's base to produce water and a salt (an ionic compound): HCI(as) + Noah(as) O acid base H2O(l) + Niacin(as) water salt Acids can react with bases, regardless of whether the salt is soluble or insoluble. There are other types of acids and bases that can react without forming water.If the reactants and products of an acid/base reaction are colorless and soluble, it is impossible to monitor the progress of an acid-base reaction based solely on the appearance of the solutions. To help us monitor acid-base reactions, we use litmus paper to determine if a solution is acidic or basic. Litmus paper changes color depending on the presence of H+ or OH- ions in the substance being tested. Blue litmus paper turns red in acidic solutions containing H+ ions, and red litmus paper turns blue in basic solutions containing OH- ions. Age 2 of 12 Oxidation/Reduction Reactions In an oxidation/reduction reaction, electrons are transferred from one reactant to the other. In the simplest form of these reactions, single-displacement reactions (also called single-replacement reactions), metal ions react with pure metals. If the reaction proceeds, the pure metal gives electrons to the metal action. This causes the pure metal to become a action and the action to become a pure metal. The action must always have an anion partner which is present either in an ionic solid or in a solution.For example: MGM(s) + 2 Gag+(as) 0 2 Gag(s) + MGM+(a s) metal action If the charge of an element is changing, that is a good indication that an oxidation/ reduction reaction is taking place. Later in the semester you will learn about oxidation numbers which are used to keep track of more complicated oxidation/ reduction reactions. Step l: Chemistry The different copper species obtained in each part is shown in Equation 1 below: cue(S) Part I cue+(as) Part II part Ill cue(S) part Part V blue l.Oxidation Copper Metal with Concentrated Nitric Acid, HON.(as) The first step involves transforming Cue metal to copper(al) ions, Cue+, using concentrated nitric acid, HON.(as). At the same time, the nitrate ions (NON-) undergo a series of reactions to form nitrogen monoxide, NO. This product rapidly reacts with oxygen in the air to form NON, a brown gas. The presence of Cue+(as) makes the solution blue. When the reaction mixture is diluted with water, the Cue+ ions are hydrated (surrounded by water) to form the octahedral complex ion, [Cue(H2O)6 ]2+, as shown below.Six water molecules (shown as red O and white H atoms) are bonded to a Cue+ ion (shown in gray as the central atom). Cue+(as) + 6 H2O(l) 0 [Cue(H2O)6]2+(as) Figure 1 page 3 of 12 Step II: Chemistry II. Precipitating Cue(OH)2(s) with Noah(as) In Part II, two reactions are carried out by adding Noah(as). In the first reaction, the hydroxide ions (OH-) from the Noah(as) neutralize the excess hydroxide ions (HUH+) feet over from the previous part: HUH+(as) + OH-(as) 2 H2O(l) Once all the HUH+ ions are neutralized, additional OH- ions react with the Cue+ ion to form Cue(OH)2 precipitate. Once all the Cue+ ions have reacted, no more precipitate forms.Adding more OH- ions makes the solution basic, so it can turn red litmus paper blue. Figure 2 on the next page shows the step-wise reaction of Cue+ with Noah. Figure 2: Step-wise Illustration of the Precipitation of Cue(OH)2 in Part II – Remember: [Cue(H2O)]2+ indicates the same substance as Cue+. 1st Beaker: At the end of Part I, hydrated copper complex, Cue+ are present, making he solution blue, and excess hydroxide ions (HUH+) remain from the nitric acid used. 2nd Beaker: Adding Noah(as) to the blue solution results in the OH- ions neutralizing the HUH+ ions to form water: HUH+(as) + OH-(as) 0 2 H2O(l).The An+ ions and resulting water molecules are not shown. 3rd and 4th Beakers: Once all the HUH+ are neutralized, adding more Noah(as) results in the OH- ions reacting with the Cue+ to form the blue Cue(OH)2(s) precipitate shown at the bottom of the beaker. Water molecules released from the complex ion are not shown. 5th Beaker: When all of the Cue+ ions have been converted to Cue(OH)2(s) precipitate, adding more Noah(as) results in unrelated OH- ions in solution, which makes the solution basic. Red litmus paper can be used to confirm the solution is basic.Note that the solution is no longer blue since no Cue+ ions are present in the solution. Step Ill: Chemistry Ill. Converting solid Cue(OH) 2 to solid Cue In Part Ill of the sequence, the reaction mixture is heated. This transforms the Cue(OH)2 precipitate to Cue precipitate. Page 4 of 12 The Cue precipitate is separated from the solution, called the supernatant liquid, using a method called gravity filtration. The mixture is filtered using a filter funnel, ND the solid is collected on filter paper. The supernatant liquid runs through the filter paper and collects in a beaker.This resulting filtered solution is called the filtrate. Step IV: Chemistry ‘V. Dissolving Cue(s) with sulfuric acid, HASPS(as) In Part ‘V, the Cue precipitate is dissolved using sulfuric acid, HASPS(as). This redo reaction returns copper to its aqueous phase. Step V: Chemistry V. Reducing Cue+ ions with Zinc Metal In Part V, zinc metal (Zen) is added to the copper solution to convert the copper ions back to copper metal, Cue(s). The resulting solution will contain colorless zinc ions, Zen+(as) and copper solid. Visible evidence of this reaction is observed as bubbles of gas being released from the solution. Since the HUH+ ions do not dissolve the Cue metal, the amount of copper yielded is not affected by excess acid. ) Identify the gas displaced from the acid in this reaction. When the solution becomes colorless, all of the Cue+ ions have been converted to Cue metal. All of the excess Zen metal is also converted to Zen+ ion by the excess HUH+ ions from the sulfuric acid, HASPS(subdued to dissolve the Cue precipitate in Part IV. Once all the Zen metal is dissolved, the Cue metal can be isolated by decanting, or pouring off, the supernatant liquid. The Cue will then be rinsed, dried, and weighed as described in the procedure. Age 5 of 12 In this experiment, you will carry out a series of reactions starting with copper metal. This will give you practice handling chemical reagents and making observations. It is typical for scientists to observe materials before they react, what happens during a reaction and how it lo oks when the reaction has come to completion. The product of the final reaction will be copper metal and the percent copper that is recovered will be calculated. **Lab Notebook** You should include one table that contains the mass of copper at the beginning and ND of the experiment along with % of copper recovered.This table should include: Mass of copper at the start of experiment (in Part l) Mass of copper + evaporating dish (from Part V) Mass of empty evaporating dish (from Part V) Mass of copper recovered (from Part V) Percent of copper recovered Record observations for each of the steps (I-V) of the copper cycle in your lab book. Be sure to label each step (I-V). The observations for each step should include: the appearance of the reactants before the reaction the appearance of the reactants during the reaction (for example, bubbles, flames, etc. The appearance of the products after the reaction.Your observations should include state(s) of matter, color, texture, smell, etc. Wh ere applicable. If your observations are not detailed, you may not receive full credit. One step also requires a specific chemical test using litmus paper to check for acidity. Be sure to also record the results of these tests in your lab notebook. **You will turn in worksheet pages 11-12 along with the duplicate pages from your lab notebook. Step l: Procedure – Oxidation Cue with concentrated nitric acid, HON.(as) 1 . Place a sample of weighing paper in the balance. Tare the balance, so it reads 0. 0000 g. Use forceps to transfer about 0. 5-0. 40 g of Cue strips onto the weighing paper. Record the mass of the Cue strips. Transfer the Cue strips into a clean 250-ml beaker labeled with one of your group member's initials. Record the appearance of the copper metal in your lab report. CAUTION: Concentrated nitric acid is highly corrosive, so it can cause severe chemical burns and damage clothing. Handle with care and avoid breathing the fumes. Any nitric acid spilled on skin mus t be rinsed immediately with water for 15 minutes. Any acid spilled on your work area must be neutralized then the entire rear should be washed and dried.CAUTION: Concentrated nitric acid reacts with copper metal to form brown toxic NON gas. Leave the reaction beaker in the fume hood until all of the brown gas is vented in the hood. ICC CHEM. 151 AL: The Copper Cycle page 6 of 12 2. In a fume hood, use a 10-ml graduated cylinder to carefully measure about 3 ml of concentrated nitric acid, HON.(as). Slowly pour the nitric acid onto the Cue strips in the beaker, swirling the beaker to maximize contact between the Cue and nitric acid until all of the solid Cue has dissolved and the NON gas has escaped.Keep the action beaker in the hood until all the toxic brown NON gas is gone, and keep your face away from the hood to avoid inhaling nitric acid fumes and NON gas. Describe the reaction between HON. and the Cue metal in your lab report. 3. Dilute the resulting solution with about 10 ml o f denizen water. Describe the appearance of the resulting solution containing Cue+ in your data table. Step II: Chemistry – Precipitating Cue(OH)2(s) with Noah(as) left over from the previous part. Once all the HUH+ ions are neutralized, additional OH- ions react with the Cue+ complex ion to form a gelatinous blue Cue(OH)2 precipitate.Once all the Cue+ ions have reacted, no more precipitate forms. Adding more OH- ions makes the solution basic, so it can turn red litmus paper blue. The picture sequence on the next page outlines the step-by-step process that occurs during this step. Step II: Procedure – Precipitating Cue(OH)2 with Noah solution CAUTION: Sodium hydroxide (Noah) can easily damage eyes. It is corrosive and can cause chemical burns and damage clothing. Any Noah splashed into eyes or spilled on skin must be rinsed immediately with water for 15 minutes. Any base spilled on your work area must be neutralized then the entire area should be washed and dried. Whil e constantly stirring the Cue solution, slowly add MM Noah(as) from the dropper bottles. First, the OH- from the Noah added will neutralize the excess acid left over from Part l. 2. Once all the acid is neutralized, additional OH- ions react with the Cue+ to form Cue(OH)2(s), a blue precipitate. Record what you observe in your lab report. When adding more Noah does not produce more precipitate, the solution can be tested to determine if all the Cue+ has been precipitated and additional OH- has made the solution basic. Use red litmus paper to test if the solution is basic as follows.Without stubbing any precipitate, use a glass stir rod to place a drop of solution (NOT the precipitate) on a piece of red litmus paper. If it turns blue, the solution is basic. Stop adding Noah when the solution turns red litmus paper blue. Describe your litmus test in your lab report. Page 7 of 12 Step-wise Illustration of the Precipitation of part II 1st Beaker: Check solution using red litmus paper (r efer to background handout). Continue adding base until solution is basic. At the end of Part I Cue+ ions are present, making the solution blue, and excess hydroxide ions (HUH+) remain from the nitric acid used. D Beaker: Adding Noah(as) to the blue solution results in the OH- ions ions are not shown. 3rd and 4th Beakers: 5th Beaker: Once all the HUH+ are neutralized, adding more Noah(as) results in the OH- ions reacting with the Cue+ to form the blue Cue(OH)2(s) precipitate shown at the bottom of the beaker. When all of the Cue+ ions have been converted to Cue(OH)2(s) precipitate, adding more Noah(as) results in unrelated OH- ions in solution, which makes the solution basic. Red litmus paper can be used to confirm the solution is basic. Note that the solution is no longer blue since no Cue+ ions are present in the solution.In reality, your solution may still appear blue because of the dispersion of the Cue(OH)2 in the solution by mixing. Step Ill: Procedure – Converting Cue( OH)2(s) to Cue(s) 1. Set up a ring stand as shown in the figure at the right. Set up a ring clamp, and put a wire gauze on top of it. Above it, attach another ring clamp with a diameter large enough to go around a 250-ml beaker. You are going to set your 250 ml beaker on the lower ring and gauze. The upper clamp will hold the beaker in place so it does not fall. 2. Add about 30-40 ml of denizen water to your reaction beaker from Part II.Carefully place the beaker on the ring stand inside the upper ring. CAUTION: Gently heat the beaker over a medium flame. (Set the inner cone of the Bunsen burner flame to a height of about 1. 5 inch and the lower ring stand about 4 inches above the top of the Bunsen burner). Constantly stir the solution with the glass end of the stirring rod until all the blue precipitate turns black, and the solution is clear. If the solution starts to bump or boil, immediately remove the beaker from the heat and let the solution cool slightly. Describe what happens to the Cue(OH)2 precipitate upon heating in your lab port. Age 8 of 12 3. Allow the beaker and contents to cool. While they are cooling, set up the gravity filtration apparatus. Obtain a second ring stand, and attach a ring clamp that is small enough to hold the plastic funnel. Prepare the filter paper as shown below: Finally, place the plastic funnel in the small ring clamp, and place a 400-ml beaker beneath it to collect the filtrate (the liquid that goes through the filter paper). The funnel's stem should be Just inside the beaker to prevent splashing. 4. Use the markings on a clean 150-ml beaker to measure out about 25 ml of denizen water.Boil the water on a hotplate to wash the precipitate in step 6. 5. When the 250-ml reaction beaker has cooled to room temperature, pour the Cue precipitate into the funnel to filter the contents. Transfer the last traces of the solid from the reaction beaker into the funnel, using a stream of denizen water. 6. Use a disposable pipette to wash the precipitate on the filter paper using the hot denizen water heated in the 150-ml beaker. Allow each portion of hot water to drain through the filter paper into the beaker below before adding the next portion. Use 15 ml of the hot denizen water to thoroughly wash the Cue precipitate.

Thursday, January 9, 2020

The Great Gatsby Compared to the Wasteland - 1255 Words

Fitzgerald s Great Gatsby and Elliot s The Wasteland are two stories that similarly express the modernist post-war disillusionment. Both stories comment pessimistically on the direction that our world is moving in from the post-war modernist perspective. Both men looked past the roaring twenties, and realized that this time period was actually a moral wasteland. The final paragraphs of The Great Gatsby sum up their mutual lack of faith in American culture to improve. Fitzgerald uses a number of both direct and indirect ways to comment on what has happened to America. The green light is a recurring symbol in this book that has many deep meanings. Beginning in the first chapter, when Nick compares the green bulk of America rising†¦show more content†¦The people who first came to America had the green in their eyes as well, and they were corrupted by the opportunities that America had to offer. This paragraph also shows that it was the green light and the dreams of Gatsby which cut down the pure fertility of this place in lieu of riches and materialism. The paragraph continues to discuss the natural brilliance of America, and that the people who came were initially amazed by this. This amazement was evanescent, and the people who came to America began to follow the green light, resulting in this wasteland. And as I sat there, brooding on the old unknown world, I thought of Gatsby s wonder when he first picked out the green light at the end of Daisy s dock. He had come a long way to this blue lawn and his dream must have seemed so close that he could hardly fail to grasp it. He did not know that it was already behind him, somewhere back in the vast obscurity beyond the city, where the dark fields of the republic rolled on under the night. In this paragraph Nick looks back to Gatsby and his pursuit of the green light. He says that Gatsby s pursuit of daisy was corrupted by materialism, and that his dream was close enough that he could feel it. Nick expresses a longing for the past in this paragraph, and expresses that inShow MoreRelatedSymbolism Of The Great Gatsby By F. Scott Fitzgerald1130 Words   |  5 Pagesmeaning to the mind of the readers. The reader is forced to think, make connections, and succeed in adding a new meaning to the novel. F. Scott Fitzgerald is a master of hiding deeper meanings behind a text as clearly showcased in the novel The Great Gatsby. The â€Å"iceberg theory† describes that only around 20% of the story is directly revealed through text. In comparison to an actual iceberg, that is usually the portion of the floating ice mountain that is visible above water. The other 80% of theRead MoreThe Equality Myth Essays656 Words   |  3 PagesIts pretty hard to tell what does bring ha ppiness. Poverty and wealth have both failed. --Kin Hubbard, Sociologist The Great Gatsby written by F. Scott Fitzgerald is as much a novel about social hierarchy as it is about class-consciousness. Throughout the novel we are bombarded with images of extravagant wealth and shuddering pauperism with the elite upper class using those around them as stepping-stones to their own selfish happiness. The novel makes a point to differentiate between classesRead MoreEssay Symbolism in The Great Gatsby864 Words   |  4 PagesIn the novel, The Great Gatsby, there is lots of reflection on symbolism, and especially colored symbolism. In this novel symbolism is a very important factor, it shows the difference between the different characters and scenes in the novel. The color green influences the story a lot. Green shows many thoughts, ideas, attitudes, and choices that Gatsby has throughout the story. White too plays an even more important role in the novel as it is used to represent some of the characters, it also talksRead MoreLions And Sheep By. Scott Fitzgerald s The Great Gatsby1096 Words   |  5 Pagesare prime examples in F. Scott Fitzgerald’s The Great Gatsby of an ascendant and inferior. Tom is a vastly wealthy man who foils George’s personality and traits. He asserts dominance on George by taking his wife as his mistress. He and others push George to submis sion as well. Tom is naturally born into wealth and prosperity where George has no choice but to labor his way to what little claim he has in the world. He resides in a desolate wasteland of a setting in a run down garage unlike Tom, whoRead MoreAnalysis Of The Book The Great Gatsby Essay1060 Words   |  5 PagesReview Sheet 1. Title: The Great Gatsby Significance of title: The title of the book is ironic in the sense that Gatsby, the main protangonist of the story, has gained wealth and celebrity like status in the West Egg only with the help of shamming others and deceiving those around him. In the end, Gatsby is dead and the empire of wealth and reputation has shattered despite how great he is. 3. Author: F. Scott Fitzgerald Characters 4. Protagonist(s): Jay Gatsby 5. Antagonist(s): 1.Tom BuchananRead MoreAnalysis Of The Book The Great Gatsby 1138 Words   |  5 Pagespeople in the United States. The novel The Great Gatsby documents this time period with a precise attention to the culture clash that resulted from this era. This culture clash is emphasised by the climax of the novel, with a conflict between Gatsby and Tom Buchanan. The division of East and West Egg due to geographic and sociopolitical factors provides the initial preconceptions necessary to spark the main conflict of the novel between Tom Buchanan and Gatsby. The most important fact in establishingRead MoreEssay on Symbols of The Great Gatsby 1249 Words   |  5 PagesFitzgerald captured this era in his book, The Great Gatsby. Through his many symbols he illustrates the hopes, the forgotten God, and the oppressed Americans of the Twenties. The symbols in The Great Gatsby help convey several different themes, from wealth to loss of morals, to poverty. The green light in The Great Gatsby is an ambiguous symbol. The green light is deceiving at first, tricking the reader into thinking it is merely a symbol of hope. â€Å"Gatsby believed in the green light, the orgiasticRead MoreEssay about The Great Gatsby and The Sun Also Rises 2160 Words   |  9 Pageson the surface. Despite the highs experienced by much of the country, it wasnt without its problems. Crime violence was benevolently running the streets and the Speakeasies beyond the reach of full Prohibition, the world was being set-up for The Great Depression, and America was brimming with members of the Lost Generation. This generation and the hypocrisies and idiosyncracies of the American Dream inspired a rising and influential set of artists, poets and writers, and a list of best-sellingRead MoreThe Great Gatsby By F. Scott Fitzgerald1198 Words   |  5 Pagescity in his novel The Great Gatsby. The setting is on Long Island and New York City in the early 1920’s sho rtly before the start of the great depression. This novel continually compares the fictional cities of East Egg and West Egg. These cities represent the two different sides of Long Island. The repeated comparison of the society and class distinction on the East side versus the West side of Long Island shows the difference that earning your wealth has on your morality compared to being born intoRead MoreA False Image Of Freedom : The American Dream1515 Words   |  7 Pagesnow, and has inspired them to seek a lifestyle that excels their current one. However, this idealistic belief possesses a biased and dishonest nature that is undetectable to those blinded by this idea . F. Scott Fitzgerald, through his novel The Great Gatsby, lifts the veil on this American Nightmare, and shows readers it’s true nature. Rooted directly to the Declaration of Independence in 1776, the concept of the American Dream claims that all men are born equal and possess the right to pursue happiness

Wednesday, January 1, 2020

Heroism Within Scarlet Letter - Free Essay Example

Sample details Pages: 4 Words: 1067 Downloads: 6 Date added: 2019/05/18 Category Literature Essay Level High school Tags: The Scarlet Letter Essay Did you like this example? Heroes are the main characters of every aspect of peoples lives. They can be seen in media, in fictional stories, and in everyday lives. A prime example of another hero readers see is within The Scarlet Letter, by Nathaniel Hawthorne, which is a novel in which heroism is found in the shamed. Don’t waste time! Our writers will create an original "Heroism Within Scarlet Letter" essay for you Create order Shunned and heroic people are almost never one of the same. Usually, it is one against the other. Even so, Hester, through her shame and rejection, is named a hero. Hester is originally portrayed as a scapegoat and later becomes a hero, which is shown through how the bearer of the scarlet letter is treated throughout the book, the stereotypical plotline of a heros journey, and the connection between other heroes and Hester. Over the course of the book, Hester has immense guilt and shame placed upon her, much of which she does not deserve. When Hester makes her first appearance, she is seen walking out of a prison. The information that the reader is given concludes Hester has committed a crime and must be publicly shamed for committing it. This is characterized through Hester gripping her child tightly to her chest, not so much by an impulse of motherly affection, as that she might thereby conceal a certain token (Hawthorne 55). The fact that a mother would grip her child so tightly, just to conceal the guilt placed upon her, shows how her being blamed has an effect on her relationships with other people. Walking out of a prison immediately relates Hester to being an outcast, as prison is societys most obvious way of shunning. The witnesses of Hester Prynnes disgrace had not yet passed beyond simplicity (Hawthorne 59), each ignoring her and actively treating her with complete biased disrespect. This is t he beginning of her shunning, leading up to the beginning of her heroic story. Hester being an outcast is proved in many different ways, but the physical description of the townspeople, which is mentioned above, is the strongest evidence. Her being an outcast pushes her to the edge of town, and towards the edge of her newest story. Hester is also characterized as a hero through the stereotypical arc and backstory. A hero can be defined as many things and in many ways. A quote from Joseph Campbell from A Hero With a Thousand Faces states, A hero is any male or female who leaves the world of his or her everyday life to undergo a journey to a special world where challenges and fears are overcome in order to secure a quest, which is then shared with other members of the heros community(Campbell). Following this definition, a hero needs to leave their original home, go on a journey, face challenges and fears with others in the community and secure a sort of reward. Hester comes to Boston, Massachusetts from her original daily life; commits adultery, causing her to go on a quest of redemption; face the challenges of social exile, being a single mother and guilt; she then overcomes all this and is reward by having all her crimes forgiven by the community. All this can be shown through multiple examples, but the main point for a hero is the challenge: While its comparative remoteness put it out of the sphere of that social activity. In this little, lonesome dwelling, with some slender means that she possessed, and by the license of the magistrates, who still kept an inquisitorial watch over her, Hester established herself, with her infant child (Hawthorne 84.) This quote well portrays some main challenges that she must face, from social exile to taking care of the child and supporting her. This furthermore proves Hester is indeed a hero following a heros journey. Heroes are not a new concept; they have been around forever. For every hero, there is a symbol: for Superman, his symbol is an S; for Wonder Woman, two Ws stacked upon one another; and for Robin, an R. All of these vary but are a symbol of their story and who they are. Hester has a symbol as well. It starts off symbolizing adulterer and was only considered a mark of sin. As the years pass, it comes to have a different meaning: Such helpfulness was found in her so much power to do, and power to sympathize that many people refused to interpret the scarlet A by its original signification. They said it meant Able; so strong was Hester Prynne, with a womans strength (Hawthorne 168). Adultery and able have two very different meanings, but through this, Hester is becoming portrayed more as a hero, helping the sickly and the poor. Hesters acts are so kind-hearted the townsfolk start praising her in front of outsiders, instead of spreading horrible rumors and whispering words of disgust about her. This resembles the mistake of how Supermans S means hope, but everyone thinks it means super. The new meaning of her letter adds to her being a hero throughout the story, giving her a mark to be known by. Pearl only knows her mother with the mark on her chest, never knowing what it meant, but that it was how she identified her. This is proven when Hester cast off her letter, and her daughter doesnt recognize her. She [takes] up the scarlet letter, and fastened it again into her bosom . Dost thou know thy mother now, child?. Yes; now I will! answered the child, bounding across the brook, and clasping Hester in her arms. Now thou art my mother indeed! And I am thy little Pearl! (Hawthorne 220-221). The letter became her reputation, her secret identity, and without her wearing the letter, no one knew who she was. Therefore, Hesters scarlet letter was her heroic symbol, furthermore making her a hero. It can be seen throughout the entirety of the text that Hester was simply a scapegoat for all the blame to be placed on, but through overcoming challenges, and having a new meaning for her symbol, she became a hero. She is easily compared to an arc of the stereotypical hero and can be used as an example for future reference as a hero herself. She overcomes the entire storyline of the novel after her transgressions. If Hester can overcome shame, guilt, social exile, and still become a hero, whos to say what is possible? Works Cited Campbell, Joseph. The Hero with a Thousand Faces. Pantheon Books, 1949.